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Fanboyism aside, how is it that DIRECTV is only managing to wring 5-6 channels out of 36MHz of satellite bandwidth?

The answer (nor understanding thereof) has nothing to do with what provider anyone subscribes (or doesn't subscribe) to so there's really no need to visit there.

For reference, Blu-ray is around 24MHz.

This makes no sense.As for 5-6 HD channels per 36 MHz BW, it has everything to do with the modulation type they're using."For example" if it was the same as ATSC, then it would manage easily 6-7, 19.2 Mb/s channels.

Fanboyism aside, how is it that DIRECTV is only managing to wring 5-6 channels out of 36MHz of satellite bandwidth?

The answer (nor understanding thereof) has nothing to do with what provider anyone subscribes (or doesn't subscribe) to so there's really no need to visit there.

For reference, Blu-ray is around 24MHz.

The key isn't as much the MHz as the data bandwidth per transponder, which is about 38Mbps as best we can tell. The translation form MHz to Mbps depends on the engineers desire for quality considering weather and the technology available, along with the type of transponder/license (Ka).

The key isn't as much the MHz as the data bandwidth per transponder, which is about 38Mbps as best we can tell. The translation form MHz to Mbps depends on the engineers desire for quality considering weather and the technology available, along with the type of transponder/license (Ka).

Each type of modulation has its pros & cons and another example is my U-who that has 64 Mb/s while using 7.5 MHz BW.

Hardware vendors have been known to gild the lily, certainly. . . but if you take the presentation seriously (and the presentation was not produced by DirecTV), 6Mbps x 6 = 36Mbps. Pg 27/28. As Sixto notes above, best calculations have the newest D* birds at 38Mbps per TP. Those calculations took place *before* the latest move to 6 HD per TP, so cannot be accused of trying to reach a pre-determined result to fit a theory.

So, you can bag on D* all you like, and cry "fanboy!" to your heart's content, but it isn't just D* saying this is possible with the latest/greatest encoders; it is also Ericsson.

Therefore, before you start doing the fanboy j'accuse, you better either disprove 38Mbps, or go after Ericsson credibly as liars.

A couple of differences between ATSC and the SAT modulation is my TV needs more than 13 dB SNR to stay locked without errors, while the SAT works down to about 8 dB CNR.

Wow what modulation rate works down to 13 dB SNR? 256QAM has a MINIMUM of 32 dB and that's 38.8mbps in a 6 MHz wide channel. Helps when cable is a closed system though. I've had SNR's as high as 40 before on DOCSIS channels, though they hover around 37, 38.

Wow what modulation rate works down to 13 dB SNR? 256QAM has a MINIMUM of 32 dB and that's 38.8mbps in a 6 MHz wide channel. Helps when cable is a closed system though. I've had SNR's as high as 40 before on DOCSIS channels, though they hover around 37, 38.

OTA needs to work with weaker signals, than a CATV system.My OTA can be as high as 28-30 dB SNR.

My U-Who runs at 28-29 dB "noise margin", but their minimum is around 12 dB, and maybe even 9 dB.

The satellite also includes wideband (i.e., 165 MHz) uplink and downlink channels

The emission designators of the signals to be transmitted through these channels are: 24M0G7W, 36M0G7W and 54M0G7W with associated allocated bandwidths of 24 MHz, 36 MHz and 54 MHz, respectively.

The downlink antenna for the 19.7-20.2 GHz band is a 1500 element active phased array. This array is extremely flexible and can be configured from the ground to create up to twenty-four 0.5° spot beams, a single wide area CONUS beam, or virtually any beam combination in between these two extremes.

The downlink antenna for the 19.7-20.2 GHz band is a 1500 element active phased array. This array is extremely flexible and can be configured from the ground to create up to twenty-four 0.5° spot beams, a single wide area CONUS beam, or virtually any beam combination in between these two extremes.

While phased array can be quite flexible, The CONUS beam testing didn't turn out to be too successful.

In the end, measuring what bandwidth DirecTV is actually using might be of more use.

I would be curious to know what bitrate and whether or not they are using the new encoders for the Audience Network. The picture quality is quite bad on tonight's Damages premiere. Lots of artifacting.